Work to remove around 14,000 tonnes of silt from Canning Half Tide Dock in Liverpool is due to start next week, ensuring the vital amenity is accessible for the many deep-drafted vessels and international boating events that use the city’s docks.
The Canal & River Trust have been carefully planning the £1 million project for the last 18 months, working with agencies and landowners including Marine Management Organisation and Peel Ports.
Silt has been building up in the dock, coming in from the River Mersey through the lock gates, since the last time it was dredged in the 1990s and is now several metres thick.
77 blue whales
The Canal & River Trust plan to remove silt, weighing equivalent to around 77 blue whales, from across the whole area of the dock, to increase the water depth to around seven metres. The material will be pumped back into the River Mersey, with the set up ensuring that the rate and particle suspension will have minimal impact on the existing concentration and flows.
Mark Weatherall, senior project manager explained: “This essential work is just one of the many ways our charity cares for Liverpool South Docks.
“Canning Half Tide Dock is a vital amenity not only for visiting boaters but for world-class racing and tourist events, and part of a World Heritage site, so it’s important to keep it in top condition.
“In preparation for the work we have monitored and assessed the environment within the Liverpool South Docks system and the River Mersey, including studies on sediment, water and wildlife, to ensure that we’re reducing any impacts on the surrounding environment and protecting the historic value of the dock.
“The equipment itself looks like a big hoover on a boat, and from the surface you won’t be able to see the difference it makes, but the impact for larger boats will be substantial and long-lasting.”
Work is expected to take around six weeks, with one day off in every seven to allow boaters to move their vessels in line with high tides.